diff --git a/m4/ax_check_qt.m4 b/m4/ax_check_qt.m4
index ec0c366..588706e 100644
--- a/m4/ax_check_qt.m4
+++ b/m4/ax_check_qt.m4
@@ -84,7 +84,7 @@ AC_DEFUN([AX_CXX_CHECK_QT], [
   AM_CONDITIONAL(HAVE_$1, test $HAVE_$1 -eq 1)
   AC_SUBST(AM_CPPFLAGS)
   AC_SUBST(AM_CXXFLAGS)
-  AX_QT_RULES='
+  ADDITIONAL_QT_RULES='
 %_ui.hxx: %.ui
 	${UIC} -o [$][@] $<